HBASE-14995 Optimize setting tagsPresent in DefaultMemStore.java (huaxiang sun)

hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/DefaultMemStore.java

@@ -240,7 +240,7 @@ public class DefaultMemStore implements MemStore {
     // When we use ACL CP or Visibility CP which deals with Tags during
     // mutation, the TagRewriteCell.getTagsLength() is a cheaper call. We do not
     // parse the byte[] to identify the tags length.
-    if(e.getTagsLength() > 0) {
+    if (!tagsPresent && (e.getTagsLength() > 0)) {
       tagsPresent = true;
     }
     setOldestEditTimeToNow();